So this is a new problem. Envoy has been running good without any problems. Then when I came out and started it after dinner tonight, it was running really rough. So I putted it home, didn't seem to have any trouble going. No fault lights, all gauges okay. Let it run in my driveway for a little and it would intermittently jerk, but not a constant rough idle. Turned it off and checked all fluids. Turned it back on and same thing. But then when I turned my ac off, it quit jerking. Turned the ac back on, and still ran fine. AC has been working fine, and still does. Anybody have any ideas of known causes of this? Or do I just need to wait for it to happen again or get worse? Thanks for any help